RE: stable hover
I had an axe that I learned the basics on but I gave it to my brother. He is trying to work his way through it now. Really is a tough little bird to fly. Makes it a PITA to learn that tail control and the roll/pitch controls at the same time.
I am sure the battery and all that will help but the axe really is not worth all that cash in upgrades, most of which you probably won't take with you.
Those 1320 bats are going to be too small to use on a 450 class heli if you don't want to be in the same 3-4 minute flight times that you get out of the stock axe junkpack. The gy240 is probably going to a little bit under par if you plan on eventually going to a bigger bird. Brushless upgrades....hmm if I had too much money on my hands that I didn't know what to do with it all.
I spent enough on spare parts, learned the basics and thats all. Moved up to a mini-titan and instantly felt it was so much easier to control that I can't imagine how heli-max can sell the axe like it is. If they want people to grow in the sport (and maybe buy one of their bigger birds you would think they would make a quality product from the bottom up or not make it so as to not tarnish their rep).
I know I will never ever ever purchase another heli-max heli, I don't care how good any of their other helis might be. I feel stiffed in some ways by the axe and its cheap parts (cheap as in poor quality). They really screw their customer. If your e-board goes out what can you do, pay 85 for a new one (on an entire heli that cost 200 bucks) or go brushless and spend 250 to do it.